The pictures seen below, besides just being of general
interest, should clearly show why one of the carts from a given cartridge
family will not plug into any other family's game console. The circuit
boards inside are radically different; not even remotely close to being
able to work together, even if the ROMs inside are alike.

Picture title

Size

Description

74k

A visual comparison of all four of the different types and style of
carts and/or cart families. (See FAQ.)

MPT-03 cartridge (upper left)

Palladium cartridge (upper right)

Emerson family, long style (lower left)

Emerson family, short style (lower right)

24k

As is typical for this "system" not long after I thought I had identified
all of the "ROM-compatible" Emerson clone families, another one popped
up. This is what a normal Ormatu family cartridge looks like. (To help others
identify the case style, here is an inside
view.)

32k

The insides of a Palladium cartridge. (Chip removed merely for visual
purposes.) Back side of
cart here. Note that the cartridge has "Polybrain cartridge"
etched into it. Every Palladium cart I've seen has this.

38k

A scan of the very rare Grandstand cart "Combat". Here is the
back side of the cart, along with
the inner circuit board's front side
and back side. (This cart was loaned to
Ward by a New Zealand collector. It was an MPT-03 cartridge, in a cheaply-made
case unlike any other case style we have ever seen.)

87k

Two cartridge guts (Emerson and MPT-03) sitting side-by-side. I
included a machinist's rule as a size reference. This helps to show how
radically different the cartridge
families are internally, and why they cannot be plugged into each
other's game systems. The cartridge circuit board shown on
the left side is from an Emerson family game. The circuit board shown
on the right side is from a "Grandstand" (pirate?) company game. Its board
layout is a simplified version of the MPT-03's; if a wire trace was not
really connected, they simply deleted it.

54k

A 150 dpi scan of the other side of the Grandstand cart that is
shown in the picture above. ("Crazy Climber".) You can clearly see
that all but two traces are on this rear side. Note also the "Orbit"
name etched into the rear of the circuit board.

60k

This is the front view of an official MPT-03 cart. ("Auto Race" if you
must know.) Here is the rear view
as well. This is a factory-made, unmodified cartridge; those huge jumper
wires were not added later on by a hobbyist. You can see some fairly
obvious hand-soldering in places, too. Note that although the front
view makes it appear like there are many wire traces, that most of them
"dead-end" inside the plastic casing of the cartridge itself. Only 2
are really connected on one side.